Studies on the Intermolecular Hydroarylation of N-Ts- or N-Ac-Protected Indoles and 2,3-Allenoates
作者:Zhao Fang、Chunling Fu、Shengming Ma
DOI:10.1002/ejoc.201001661
日期:2011.3
An operationally simple, TFA-promoted regioselective hydroarylation reaction of 2,3-allenoates with N-Ts- or N-Ac-indoles to afford 4-indolyl-4-arylbut-2-enoates is described. A series of substrates was tested, and the E/Z selectivity was found to depend on the reaction temperature and time. A mechanism involving the formation of E and Z allylic carbocations generated in situ from the reaction of 2
Controlled Reactions of 2,3-Allenoates with a 1,3-Diketone Catalyst Effect
作者:Zhao Fang、Chunling Fu、Shengming Ma
DOI:10.1002/ejoc.201101852
日期:2012.5
Two types of reactions of 2,3-allenoates with 1,3-diketones under different reaction conditions are described: under palladium catalysis, the relatively electron-rich C=C bonds are attacked to afford ethyl (2E)-4-acyl-2-alkyl-4-aryl-6-oxohept-2-enoates exclusively with dicyclohexyl(2,4,6-trimethoxyphenyl)phosphane as the ligand; under Cu(OAc)2 catalysis, 4-[R–C(=O)–]-(LB-Phos) 3,5-dialkyl-3-(2-oxo
Intermolecular sequential [4 + 2]-cycloaddition–aromatization reaction of aryl-substituted allenes with DMAD affording phenanthrene and naphthalene derivatives
作者:Xuefeng Jiang、Wangqing Kong、Jie Chen、Shengming Ma
DOI:10.1039/b808767a
日期:——
An efficient entry to phenanthrene and naphthalene derivatives through intermolecular sequential [4 + 2]-cycloaddition-aromatization reactions of aryl-substituted allenes with DMAD in the absence of any catalyst was discovered. In this reaction the aromatic ring and the adjacent carbon-carbon double bond of the allene unit acted as the 1,3-diene.
Reaction of 2,3-Allenoates with TsNBr<sub>2</sub> in the Presence of Base: A Facile Highly Stereoselective Synthesis of (1<i>E</i>,2<i>E</i>)-3-Bromo-4-oxo-<i>N</i>‘-tosyl-2-alkenoxylimidic Acid Ethyl Esters
作者:Ruwei Shen、Xian Huang
DOI:10.1021/jo070239z
日期:2007.5.1
A novel reaction pathway of 2,3-allenoates with an electrophile (TsNBr2) in the presence of K2CO3 to produce (1E,2E)-3-bromo-4-oxo-N‘-tosyl-2-alkenoxylimidic acidethylesters is reported. The reaction proceeds in a highly stereoselective fashion. A plausible mechanism to rationalize this reaction is also proposed.
在K 2 CO 3存在下2,3-脲基酸酯与亲电试剂(TsNBr 2)的新反应途径产生(1 E,2 E)-3-bromo-4- oxo- N'-甲苯磺酰基-2-报道了烯氧基氧酰亚胺酸乙酯。反应以高度立体选择性的方式进行。还提出了合理化该反应的合理机制。
Studies on electrophilic addition reaction of 2,3-allenoates with PhSeCl
作者:Guofei Chen、Chunling Fu、Shengming Ma
DOI:10.1016/j.tet.2006.02.053
日期:2006.5
butenolides were prepared from 2,3-allenoates and PhSeCl in the presence of water. The yields of the products depend largely on the structures of 2,3-allenoates. The addition of water is crucial for some of this electrophilic cyclization. The reaction of simple unsubstituted methyl 2,3-butadienoate afforded methyl 4-chloro-3-phenylselanylbut-2(Z)-enoate in good yield and stereoselectivity.